There was erected a new mountain observatory on the secondary peak (880m above sea level) of Mt. Unzen Nagasaki. The author has noticed that during three seasons, excepting summer, occasional temperature and humidity anomaly took place in night hours. On these occasions temperature began to rise gradually instead to fall in the evening, average hour being 21h and attained maximum during morning hours average being 1h. At the same time humidity fell instead of rising. Such anomalies appeared generally in the early epock of shifting of the continental high pressure towards east. When it shifted too far east in the Pacific, then the phenomenon was closed. The reason lis not yet clear but the authors view is that it may be due to the descending current from dry continental air, overlying the mountain and surrounding air which forms the forerunner of the travelling high pressure. By the nocturual cooling of lower air, fall wind along the slope must occur, which may pull down the upper continental air. The author examined three other hypotheses, i. e. inversion hypothesis. föhn hypothesis and land breeze hypothesis, and proved all not to be applicable.
This is an application of theories of the variability of natural phenomena which were established by Mr. S. Ono. (On the magnetic characterization of days and the variabiliy of natural phenomena; Annual Report of the Central Met. Obs. of Japan, Magnetic Observations for the Year 1916, published in 1924, Japanese Journal of Astronomy and Geophysics Vol. III, No.1, 1925, an abstract; Terrestrial Magnetism and Atmospheric Electricity, March 1924, an abstract in Japanese; this Journal Ser. 2, Vol. 3, No.5, 1925. Investigation on range of the variation of magnetic elements; Annual Report of the Central Met. Obs. of Japan, Magnetic Observations for years 1917 and 1920, an abstract in Japanese, this Journal Ser. 2. Vol. 3 No.8) Present author tried to apply these theories on the variation of temperature. He used thermograms observed at Tokyo between April 1914 and January 1915. To specify four seasons, A pril, July, October and January are selected, and in each of these months seven representative days are used in which two most disturbed days, two days without disturbances except smooth diurnal variation and three moderately disturbed days are contained. The temperature was read on curves for every 15 minutes and difference of contaive two are designated by a simbol ξ. Besides this quantity the daily range Δ is observed for each day. Numerical results to compare _??_ (the mesn of ξ), (_??_)2 (the square _??_), _??_ (the mean of square of ξ) and Δ are shown in a table which follows conalusions: Though there is an ample range of magnitude of _??_, _??_ or Δ, relations prived by Mr. Ono _??_=2(_??_)2 and _??_/_??_=1/2U hold good in cages of temperature variation. In this equation _??_ is the mean of Δ and U is the time duration without disturbance in a day and the square of the mean of daily range can be used to express the monthly or the seasonal mean variability of temperature variations. Value of 1/2U in present tesult is very near to 48. Since the unit of time for ξ is taken 15 min., U becomes 2×48×15/60 hours i.e. 24 hours. This result means that the mean duration of disturbances is negligibly short compared with a day in the case of the temperature variation.
It is well known that cool summer in Hokkaido is brought by centering of the semipermanent high pressure in Okhotsk Sea. Recently the effect of Solar activity on the position of high pressure is a subject of interests of Far Eastern meteorologists. The author had formerly noticed the correlation between the summer Pacific and winter Continental highs. In the present note he has calculated the correlation coefficients between summer temperature at Sapporo, principal city of Hokkaido, and the barometric gradient over Hokkaido and its vicinity in the same month for 18 years from 1907 to 1924. He found correlations -0.51±0.12 for June, -0.71±0.08 for July, 0.48±0.13 for August. This shows that high pressure in Okhotsk Sea lowers air temperature in Hokkaido in the way that more north lies the high in Okhotsk more cool is the temperature in Hokkaido. He also noticed that: - 1. When the high pressure of Okhotsk Sea comes so south as 50° N and its western edge lies at or more west of 145° E meridian then it cools Hokkaido. 2. When the high comes so south as 45° or more, then it is a little warmer in Hokkaido. When the high lies at 40° N then it is warm in Hokkaido. 3. When the Pacific high lies to the south of Kurile Islands it is warm in Hokkaido. 4. Generally, Pacific and Okhotsk highs have a distance of about 20° between them. 5. The Pacific high begins to form in May and as the summer advances it shifts gradually towards north and disappears in November. 6. When the Pacific appears first near Hokkaido, it has tendency to keep the position. In such years extreme hot or cool summer is usually experienced. (June 1925)